Stabilizing means for earthmoving scrapers



Oct. 14, 1969 J. L. DE BOEUF ETAL 3, 7

STABILIZING MEANS FOR EARTHMOVING SCRAPERS Fild Sept. 28, 1966 4 Sheets-Sheet 1 INVENTORS. J'AMEE. L. DEBOEUF LARRY G EFTF F\ELD RAYMOND L Most-1R BY ERN EST W. WAGNER Oct. 14, 1969 J. DE BOEUF ETAL 3,471,951

STABILIZING MEANS FOR EARTHMOVING SCRAPERS Filed Sept. 28. 1966 4 Sheets-Sheet I.\".'ENTOR$. JAM-Ls L. DEBOEUF' LARRY C EFTELFIELD RAYMOND L. MOELR E RNEST W. WAC:- NER Obi. 14, 1969 J, DE BQEUF ETAL 3,471,951

STABILIZING MEANS FOR EARTHMOVING SCRAPERS Filed Sept. 28, 1966 4 Sheets-Sheet 3 INVENTORS. MES L. DE. Boa RRY 51- FIE RAYMO L. osER z ATTORNEYS Oct. 14, 1969 DE BQEUF ETAL 3,471,951

STABILIZING MEANS FOR EARTHMOVING SCRAPERS Filed Sept. 28, l966 4 Sheets-Sheet 4 Y INVENTORS. JAMEs L. De Beau? LARRY G: EFTEF\EL.D RAYMOND L. MOSER ERNEST W. WAq-NER ATTORNEYS nited States Patent US. (1]. 37-129 Claims ABSTRACT UP THE DISCLOSURE An earthmoving scraper comprising a bowl adapted to be raised or lowered for earth loading or discharge purposes. A fioor is movably mounted in the bowl to selectively uncover an opening formed therein. A striker plate is attached to a forward end of the floor to level earth discharged from the bowl and a stabilizing skid plate is H attached beneath the floor adjacent to the striker plate to aid in stabilizing the scraper during ground leveling operations.

This invention relates to a stabilizing means for earthmoving scrapers and more particularly relates to a scraper having means arranged thereon to engage the ground for stabilizing the scraper during a discharge and spread phase of operation.

Conventional wheel tractor-scrapers oftentimes tend to oscillate laterally, relative to their direction of movement, during the earth discharge and spread phase of scraper operation. Oscillations are particularly apparent when such operation is carried forth in so-called weak soils with the scraper traveling at moderate rates of speed. Unless impeded by reducing the scrapers speed, continued increase in the magnitude of such oscillations causes the operator to lose control of the filling portion of the earthmoving cycle.

In order to overcome the above briefly discussed problem, this invention provides a stabilizing means arranged to support a scraper bowl during the earth discharge and spread phase of scraper operation. In particular, the stabilizing means preferably comprises a skid plate arranged to extend substantially across the full width of the bowl to engage the ground during such operational phase to dampen oscillatory movements thereof. In addition to such supporting desideratum, the stabilizing means further functions to aid in improving gradability of the discharged earth or other such material. The stabilizing means is preferably further arranged to be retracted away from ground level during other phases of scraper operation.

An object of this invention is to provide a stabilizing means for an earthmoving scraper arranged to engage the ground during the discharge and spread phase of scraper operation to dampen oscillatory movements thereof and improve gradability of the discharged earth.

Another object of this invention is to provide a stabilizing means in the form of a skid plate arranged to extend substantially across the full width of a scraper bowl to engage the ground to stabilize the scraper during the ejection and spread phase of scraper operation and to be retracted away from ground level during other phases of vehicle operation.

A further object of this invention is to provide a stabilizing means for an earthmoving scraper associated therewith for maintaining a flat portion of said stabilizing means substantially parallel with respect to ground level during all phases of scraper operation.

Further and more specific objects of this invention will ice become apparent from the following description and accompanying drawings wherein:

FIG. 1 is a partially sectioned side elevational view of a tractor-scraper combination employing a first stabilizing means embodiment of this invention;

FIG. 2 is an enlarged, partially sectioned side elevational view more particularly illustrating the stabilizing means employed in the tractor-scraper combination of FIG. 1;

FIG. 3 is a side elevational view similar to FIG. 1 with parts broken away to fully disclose structural arrangements of the scraper as they would appear during a discharge and spread phase of scraper operation;

FIG. 4 is a partial top plan view with parts broken away illustrating a second stabilizing means embodiment of this invention which may be employed in the tractorscraper combination illustrated in FIG. 1;

FIG. 5 is a side elevational view taken in the direction of arrows VV in FIG. 4; and 7 FIG. 6 is a partial side elevational view of a scraper bowl as it would appear with the stabilizing means illustrated in FIGS. 4 and 5 maintained in four different positions (A-D) of operation.

FIG. 1 illustrates a wheel tractor-scraper combination comprising a tractor 10 having a scraper 11 attached thereto in a conventional manner. A vertically arranged pivot pin arrangement 12 pivotally attaches a draft frame 13 to the tractor. In turn, a spreader 14 is arranged to attach the draft frame to draft arms 15. Each arm 15 (one shown) is preferably connected to the midportion of each side wall of a bowl 16 by a pivot pin 17. The bowl is secured to a frame 18, mounted for vertical pivotal movement on axle 19 which also mounts a pair of groundengaging wheels 20 (one shown). A pair of hydraulic jacks 21 (one shown) are each pivotally connected between draft frame 13 and a forwardly disposed portion of bowl 16 to permit selective raising or lowering of the bowl relative to the tractor by means of a conventional control system (not shown).

The bowl comprises a movable floor 22 terminating at its forward end in a detachable striker or strike-off plate 23 and having upwardly extending side walls 24 (one shown) attached thereto. Each wall is pivotally connected to the inside of a bowls side wall by a pin 25. The actuat ing means for selectively moving floor 22 comprises a bellcrank 26 pivotally connected to frame 18 by a pin 27 at a first end thereof and to a push rod or link 28 by a pin 29 at a second end thereof. A pivot pin means 30 pivotally connects the other end of rod 28 to a bifurcated lug member secured beneath a forward end of movable floor 22. A pair of hydraulic jacks 31 (one shown) are each pivotally connected to frame 18 by a pin 32 and to a midportion of bellcrank 26 by a pin 33. It can be seen that retraction of jack 31 from the extended position illustrated in FIG. 1 will function to pivot bellcrank 26 clockwise about pin 27 to move floor 22 rearwardl and upwardly along the back side of bowl 16 via rod 28. The floor can thus be moved to the phantom line position illustrated in FIG. 1 for earth discharging and leveling purposes.

A plate 34, constituting a cutting edge for earth scraping purposes, is detachably secured to a substantially short floor section 35 secured to the bowl. It should be understood that movable floor 22 and floor section 35 extend substantially the full width of the bowl to provide maximum support for the earth contained therein. A conventional elevator mechanism 36 may be attached to the forward end portion of the bowl in the manner illustrated so that its lower end is positioned adjacent to cutting edge 34 and its upper end is disposed above bowl 16. The above described constructions and arrangements are substantially disclosed in United States patent application Ser. No. 356,750 for Ejector Mechanism for Earthmoving Scrap- 3 er, filed on Apr. 2, 1964 by Trevor G. Campbell et a1. Such application is assigned to the assignee of the instant application.

This invention is directed primarily to a stabilizing means 37 adapted to be positioned as illustrated in FIGS. 2 and 3 during the discharging and leveling phase of scraper operation. During such an operational phase, hydraulic jacks 21 are retracted by conventional control means (not shown) to raise bowl 16 to the elevated position illustrated in FIGS. 1 and 3. Jacks 31 are also retracted by conventional control means (not shown) to move floor 22 rearwardly and upwardly in the manner above described to the position illustrated in FIGS. 2 and 3. Thus, earth retained in the bowl may be discharged freely in the manner illustrated during forward movement of the tractor-scraper. As above stated, conventional tractor-scraper combinations tend to oscillate unduly during the discharge phase of vehicle operation. In order to dampen such oscillation, stabilizing means 37, preferably comprising a fiat skid plate extending substantially the full width of the bowl, is arranged in close proximity and substantially parallel to ground level. The plate is preferably detachably secured by bolt means 38 to a support plate 39 secured to a plurality of spaced gussets 40 attached beneath movable floor 22.

Plate 37 is further constructed and arranged so that when floor 22 is rotated to the discharge position illustrated by phantom lines in FIG. 1 (to effect a predetermined spread depth), the plate will be maintained substantially parallel with respect to the longitudinal axis of the tractor-scraper and also to ground level. In addition, the plate will be maintained in substantial alignment with, but slightly above, the ground engaging portions of the scraper and tractor wheels. Such a stabilizing arrangement is particularly advantageous when the unloading or discharging phase of vehicle operation is conducted in dry or weak materials which provide limited support for the vehicle via its ground-engaging wheels. The plate has been found during the course of actual testing to provide adequate support to prevent undue vehicle oscillation. In addition, the plate aids in the scrapers grading or leveling function since it is arranged closely adjacent to the area whereat the material is discharged from the bowl.

FIG. 3 further illustrates a signal means which may be utilized to alert the operator when plate 37 is maintained substantially parallel relative to ground level, i.e., when the floor is positioned to effect the predetermined spread depth. Such signal means may comprise a conventional series circuit including a power source or battery 41, an on-off switch 42 and a visual indicator such as a light 43 arranged in the tractors cab. Thus, when bellcrank 26 is moved rearwardly to the position illustrated in this figure, switch 42 is closed to complete the circuit to illuminate light 43. Conversely, when the switch is opened, light 43 will go out to thus indicate to the operator that plate 37 is no longer maintained in its level position. It should be understood that other conventional signal means may be employed to alert the operator regarding the position of plate 37. For example, an alternative signal means is illustrated in FIGS. 3 and 5 of above-mentioned US patent application Ser. No. 356,750.

FIGS. 4-6 illustrated a second stabilizing means embodiment for the above-described tractor-scraper combination. The numerals accompanied by a prime symbol depict structures corresponding to like numbered structures disclosed in FIGS. 1-3. This embodiment essentially diifers from the aforedescribed embodiment by providing pivot pin means arranged to attach the floor actuating means and stabilizing means together for simultaneous movement relative to the floor. In particular, a movable floor 22' comprises side wall extensions 24 each pivotally supported on the inside of each of the bowls side walls by a pivot pin (not shown). A floor actuating rod 28' is pivotally connected to the floor via a pin 30' which is preferably splined to the rod and a stabilizing means 37' and journalled in bearings arranged in gussets 40. As will be hereinafter more fully described, such arrangement maintains a flat portion of the stabilizing means substantially parallel with respect to ground level during movement of the floor between its opened and closed positions.

The stabilizing means preferably comprises a two part, triangularly shaped skid plate, each part being located on opposite sides of the longitudinal center line of the scraper. The combined length of these two parts substantially equals the full width of movable floor 22' and thus the bowl. The inner end of each skid plate part is splined to pin 30' whereas each outer end thereof is pivotally mounted on a side wall extension 24' by a pin 38'. It can be seen that since pin 30' is splined to rod 28' and also to the two parts of skid plate 37' that the skid plate will freely rotate on walls 24' and gussets 40" upon actuation of rod 28'. Thus, the flat bottom portion of the skid plate will remain substantially parallel with respect to the axis of rod 28' and ground level during such actuation.

Referring to FIG. 6, fully illustrating the above parallel arrangement, when movable floor 22 is moved rearwardly from position A to position D to open the bowl, skid plate 37' pivots counterclockwise relative to the floor. When the floor is moved to position B to open the discharge opening approximately thirty-six inches for example, the flat bottom portion of the skid plate will be maintained in substantially parallel relationship with ground level. Movement of the movable floor between its fully closed position A and fully opened position D only slightly changes the angle of the skid plate with respect to ground level, as reflected in FIG. 6, primarily since rod 28' also remains substantially parallel to ground level during such movement.

It should be noted that the above-described connection of skid plate 37' to rod 28' facilitates adjustment of the plate to locate it parallel to the ground level for any desired spread depth which is dependent primarily upon the extent the floor is opened. For example, the maximum desired spread depth in FIG. 6 would be substantially equal to the distance between the flat bottom portion of plate 37' and ground level at position B. The earth discharged through the opening formed between striker plate 23' and floor portion 35 (FIG. 1) would thus tend to fill the void defined by such distance and the earth would be leveled ofi by plates 23' and 37'. Relocation of the skid plate on link 28' would function to adjust the skid plate so that it would be maintained parallel to ground level for a different desired spread depth. For example, the skid plate may be removed from pin 30', rotated counterclockwise a predetermined amount relative to the pin at position A and again attached to the pin to maintain the plate parallel to ground level at position C or D, i.e., to efiect a different spread depth.

However, it should be noted that most earthmoving applications would not necessitate such an adjustment. In particular, FIG. 6 clearly illustrates that a substantially parallel relationship will be maintained between the skid plate and ground level throughout the full range of floor movement which dictates the various spread depths which may be desired by the vehicles operator. It should be further noted that the latter skid plate embodiment does not necessarily require a signal means such as that illustrated in FIG. 3 since the skid plate is always maintained substantially parallel relative to ground level.

What is claimed is:

1. In an earthmoving scraper comprising a bowl having a discharge opening formed at the bottom thereof, first actuating means for selectively raising or lowering said bowl relative to ground level, floor means movably arranged in said bowl to open or close said opening, a striker plate attached to a forward end of said floor means and second actuating means for selectively moving said floor means relative to said bowl to an open or closed position, the invention comprising stabilizing means directly attached to said floor means to move therewith relative to said bowl, said stabilizing means comprising a skid plate attached beneath said floor means adjacent to said striker plate and providing a flat surface portion maintained in close proximity to ground level by said floor means for dampening oscillatory movements of said scraper when said second actuating means is actuated to move said floor means to an open position, movement of said fioor means to said open position placing said striker plate and stabilizing means substantially below said bowl for discharging earth from said bowl and for leveling said earth by said striker plate, and bringing said stabilizing means into an operative relation with said earth to damp oscillatory movements of said scraper.

2. The invention of claim 1 wherein said skid plate is arranged to extend substantially across the full width of said bowl.

3. The invention of claim 1 further comprising signal means for alerting an operator of said scraper when said stabilizing means is maintained in a predetermined position.

4. The invention of claim 1 further comprising means for maintaining said flat surface portion of said stabilizing means substantially parallel With respect to ground level during movement of said floor means between said opened and closed positions.

5. The invention of claim 4 wherein said means for maintaining said fiat surface portion of said stabilizing means substantially parallel with respect to ground level comprises pivot pin means attaching said second actuating means and said stabilizing means together for simultaneous pivotal movement relative to said floor means.

References Cited UNITED STATES PATENTS 2,164,461 7/1939 Le Bleu 37126 2,988,832 6/1961 Hancock 37-l29 3,328,903 7/ 1967 Campbell et al. 37129 3,343,286 9/1967 Ray et a1 37129 XR EDGAR S. BURR, Primary Examiner 

